//     Zepto.js
//     (c) 2010-2016 Thomas Fuchs
//     Zepto.js may be freely distributed under the MIT license.

;
(function($) {
	var touch = {},
		touchTimeout, tapTimeout, swipeTimeout, longTapTimeout,
		longTapDelay = 750,
		gesture,
		down, up, move,
		eventMap,
		initialized = false

	function swipeDirection(x1, x2, y1, y2) {
		return Math.abs(x1 - x2) >=
			Math.abs(y1 - y2) ? (x1 - x2 > 0 ? 'Left' : 'Right') : (y1 - y2 > 0 ? 'Up' : 'Down')
	}

	function longTap() {
		longTapTimeout = null
		if(touch.last) {
			touch.el.trigger('longTap')
			touch = {}
		}
	}

	function cancelLongTap() {
		if(longTapTimeout) clearTimeout(longTapTimeout)
		longTapTimeout = null
	}

	function cancelAll() {
		if(touchTimeout) clearTimeout(touchTimeout)
		if(tapTimeout) clearTimeout(tapTimeout)
		if(swipeTimeout) clearTimeout(swipeTimeout)
		if(longTapTimeout) clearTimeout(longTapTimeout)
		touchTimeout = tapTimeout = swipeTimeout = longTapTimeout = null
		touch = {}
	}

	function isPrimaryTouch(event) {
		return(event.pointerType == 'touch' ||
				event.pointerType == event.MSPOINTER_TYPE_TOUCH) &&
			event.isPrimary
	}

	function isPointerEventType(e, type) {
		return(e.type == 'pointer' + type ||
			e.type.toLowerCase() == 'mspointer' + type)
	}

	// helper function for tests, so they check for different APIs
	function unregisterTouchEvents() {
		if(!initialized) return
		$(document).off(eventMap.down, down)
			.off(eventMap.up, up)
			.off(eventMap.move, move)
			.off(eventMap.cancel, cancelAll)
		$(window).off('scroll', cancelAll)
		cancelAll()
		initialized = false
	}

	function setup(__eventMap) {
		var now, delta, deltaX = 0,
			deltaY = 0,
			firstTouch, _isPointerType

		unregisterTouchEvents()

		eventMap = (__eventMap && ('down' in __eventMap)) ? __eventMap :
			('ontouchstart' in document ? {
					'down': 'touchstart',
					'up': 'touchend',
					'move': 'touchmove',
					'cancel': 'touchcancel'
				} :
				'onpointerdown' in document ? {
					'down': 'pointerdown',
					'up': 'pointerup',
					'move': 'pointermove',
					'cancel': 'pointercancel'
				} :
				'onmspointerdown' in document ? {
					'down': 'MSPointerDown',
					'up': 'MSPointerUp',
					'move': 'MSPointerMove',
					'cancel': 'MSPointerCancel'
				} : false)

		// No API availables for touch events
		if(!eventMap) return

		if('MSGesture' in window) {
			gesture = new MSGesture()
			gesture.target = document.body

			$(document)
				.bind('MSGestureEnd', function(e) {
					var swipeDirectionFromVelocity =
						e.velocityX > 1 ? 'Right' : e.velocityX < -1 ? 'Left' : e.velocityY > 1 ? 'Down' : e.velocityY < -1 ? 'Up' : null
					if(swipeDirectionFromVelocity) {
						touch.el.trigger('swipe')
						touch.el.trigger('swipe' + swipeDirectionFromVelocity)
					}
				})
		}

		down = function(e) {
			if((_isPointerType = isPointerEventType(e, 'down')) &&
				!isPrimaryTouch(e)) return
			firstTouch = _isPointerType ? e : e.touches[0]
			if(e.touches && e.touches.length === 1 && touch.x2) {
				// Clear out touch movement data if we have it sticking around
				// This can occur if touchcancel doesn't fire due to preventDefault, etc.
				touch.x2 = undefined
				touch.y2 = undefined
			}
			now = Date.now()
			delta = now - (touch.last || now)
			touch.el = $('tagName' in firstTouch.target ?
				firstTouch.target : firstTouch.target.parentNode)
			touchTimeout && clearTimeout(touchTimeout)
			touch.x1 = firstTouch.pageX
			touch.y1 = firstTouch.pageY
			if(delta > 0 && delta <= 250) touch.isDoubleTap = true
			touch.last = now
			longTapTimeout = setTimeout(longTap, longTapDelay)
			// adds the current touch contact for IE gesture recognition
			if(gesture && _isPointerType) gesture.addPointer(e.pointerId)
		}

		move = function(e) {
			if((_isPointerType = isPointerEventType(e, 'move')) &&
				!isPrimaryTouch(e)) return
			firstTouch = _isPointerType ? e : e.touches[0]
			cancelLongTap()
			touch.x2 = firstTouch.pageX
			touch.y2 = firstTouch.pageY

			deltaX += Math.abs(touch.x1 - touch.x2)
			deltaY += Math.abs(touch.y1 - touch.y2)
		}

		up = function(e) {
			if((_isPointerType = isPointerEventType(e, 'up')) &&
				!isPrimaryTouch(e)) return
			cancelLongTap()

			// swipe
			if((touch.x2 && Math.abs(touch.x1 - touch.x2) > 30) ||
				(touch.y2 && Math.abs(touch.y1 - touch.y2) > 30))

				swipeTimeout = setTimeout(function() {
					if(touch.el) {
						touch.el.trigger('swipe')
						touch.el.trigger('swipe' + (swipeDirection(touch.x1, touch.x2, touch.y1, touch.y2)))
					}
					touch = {}
				}, 0)

			// normal tap
			else if('last' in touch)
				// don't fire tap when delta position changed by more than 30 pixels,
				// for instance when moving to a point and back to origin
				if(deltaX < 30 && deltaY < 30) {
					// delay by one tick so we can cancel the 'tap' event if 'scroll' fires
					// ('tap' fires before 'scroll')
					tapTimeout = setTimeout(function() {

						// trigger universal 'tap' with the option to cancelTouch()
						// (cancelTouch cancels processing of single vs double taps for faster 'tap' response)
						var event = $.Event('tap')
						event.cancelTouch = cancelAll
						// [by paper] fix -> "TypeError: 'undefined' is not an object (evaluating 'touch.el.trigger'), when double tap
						if(touch.el) touch.el.trigger(event)

						// trigger double tap immediately
						if(touch.isDoubleTap) {
							if(touch.el) touch.el.trigger('doubleTap')
							touch = {}
						}

						// trigger single tap after 250ms of inactivity
						else {
							touchTimeout = setTimeout(function() {
								touchTimeout = null
								if(touch.el) touch.el.trigger('singleTap')
								touch = {}
							}, 250)
						}
					}, 0)
				} else {
					touch = {}
				}
			deltaX = deltaY = 0
		}

		$(document).on(eventMap.up, up)
			.on(eventMap.down, down)
			.on(eventMap.move, move)

		// when the browser window loses focus,
		// for example when a modal dialog is shown,
		// cancel all ongoing events
		$(document).on(eventMap.cancel, cancelAll)

		// scrolling the window indicates intention of the user
		// to scroll, not tap or swipe, so cancel all ongoing events
		$(window).on('scroll', cancelAll)

		initialized = true
	}

	;
	['swipe', 'swipeLeft', 'swipeRight', 'swipeUp', 'swipeDown',
		'doubleTap', 'tap', 'singleTap', 'longTap'
	].forEach(function(eventName) {
		$.fn[eventName] = function(callback) {
			return this.on(eventName, callback)
		}
	})

	$.touch = {
		setup: setup
	}

	$(document).ready(setup)
})(Zepto)